noun: (sciences) Initialism of magnetic resonance tomography. [magnetic resonance imaging]
noun: (computing) Initialism of malicious (software) removal tool.
noun: (UK, Southeast Asia, Malaysia, Singapore, Philippines, Thailand, transport, uncountable) Initialism of mass rapid transit, mass rail transit, metro rail transit, or metropolitan rapid transit. A form of heavy-rail rapid-transit system that utilizes modern Electric Multiple Units to transport commuters between stations.
